3,206 research outputs found

    Rapamycin-induced inhibition of HTLV-I LTR activity is rescued by c-Myb.

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    BACKGROUND: Rapamycin is an immunosuppressive which represses translation of transcripts harbouring a polypyrimidine motif downstream of the mRNA cap site through the mammalian target of rapamycin complex. It inhibits the abnormal autologous proliferation of T-cell clones containing a transcriptionally active human T-lymphotropic virus, type I (HTLV-I) provirus, generated from infected subjects. We showed previously that this effect is independent of the polypyrimidine motifs in the viral long terminal repeat (LTR) R region suggesting that HTLV-I transcription, and not translation, is being affected. Here we studied whether rapamycin is having an effect on a specific transcription factor pathway. Further, we investigated whether mRNAs encoding transcription factors involved in HTLV-I transcriptional activation, specifically CREB, Ets and c-Myb, are implicated in the rapamycin-sensitivity of the HTLV-I LTR. RESULTS: An in vitro analysis of the role of SRE- and NF-kappaB-mediated transcription highlighted the latter as rapamycin sensitive. Over-expression of c-Myb reversed the rapamycin effect. CONCLUSION: The sensitivity of HTLV-I transcription to rapamycin may be effected through an NF-kappaB-pathway associated with the rapamycin-sensitive mTORC1 cellular signalling network.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

    Assessment for Action: An Organic, Free-Range Approach to Raising Learning for All

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    The aim of this synthesis report is to identify commonalities that can help to characterise the PAL Network’s work as a whole. More specifically, it presents: 1. The role that the PAL Network’s assessments provide in both depicting as well as improving children’s learning, i.e., assessment for action / 2. The unique strengths of the PAL Network that can enable to deliver these actions, namely its organic growth and free-range adaption. / It identifies that PAL Network members are diverse in their backgrounds, in their history with the use of citizen-led assessments, and in their evolutions from assessment to action. The Network provides a structure and platform with which to harness this diversity, using assessment for action to help raise learning for all

    Assessment for Action: An Organic, Free-Range Approach to Raising Learning for All

    Get PDF
    The aim of this synthesis report is to identify commonalities that can help to characterise the PAL Network’s work as a whole. More specifically, it presents: 1. The role that the PAL Network’s assessments provide in both depicting as well as improving children’s learning, i.e., assessment for action / 2. The unique strengths of the PAL Network that can enable to deliver these actions, namely its organic growth and free-range adaption. / It identifies that PAL Network members are diverse in their backgrounds, in their history with the use of citizen-led assessments, and in their evolutions from assessment to action. The Network provides a structure and platform with which to harness this diversity, using assessment for action to help raise learning for all

    Technical note: Development of a gradient tube method for examining microbial population structures in floating sulphur biofilms

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    Floating biofilms occur in thin layers of between 50 μm and 500 μm on the surface of certain organic, sulphidic aquatic environments and, at times, may only be several cells deep. While these structures may be important in terms of energy flow pathways, and possibly also in wastewater treatment operations, little is known about their structural/functional properties. This is due, in part, to their flimsy nature but also to methodological constraints related to their sampling and manipulation. We have investigated floating sulphur biofilms that appear as white layers on the surface of anoxic sulphidic organic wastewaters and describe here the development of a novel gradient tube method for investigating these systems. This approach enables testing of the hypothesis that these floating sulphur biofilms are complex well-differentiated structures rather than disordered dispersions of microbial biomass as has been previously thought. Furthermore, if the former is correct, they would seem to resemble the structure and functionality of comparable complex bioflms that are attached to solid substrates. The gradient tube method involves the establishment of apposing gradients of sulphide and oxygen that are expanded across a tube of agarose 10 cm in length; this simulates the oxic/anoxic interface that occurs over only several micrometres in the natural biofilm system. A plug of sulphide-enriched agarose is first placed in the base of the tube. Samples of the floating sulphur biofilm are then mixed into agarose growth medium and, before it sets, this is overlaid on top of the plug. The tubes are then open capped and incubated. A variety of different microbial populations may thus become established in the separate physiological niches that are set up in this way within the gradient tube. The populations may be quite robustly sampled by extruding and then sectioning the agarose plug. This expansion of the biofilm enables more detailed molecular phylogenetic studies of the populations found in the various niches within the biofilm and also measurement of physico-chemical parameters within the system.Keywords: gradient tube method, floating biofilms, floating sulphur biofilms, microbial ecology, sulphur biotechnology, acid mine drainage wastewater

    How big does the effect of an intervention have to be? Application of two novel methods to determine the smallest worthwhile effect of a fall prevention programme: A study protocol

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    Introduction: This project concerns the identification of the smallest worthwhile effect (SWE) of exercise-based programmes to prevent falls in older people. The SWE is the smallest effect that justifies the costs, risks and inconveniences of an intervention and is used to inform the design and interpretation of systematic reviews and randomised clinical trials. Methods and analysis: This study will comprise two different methodological approaches: the benefitharm trade-off method and the discrete choice experiment to estimate the SWE of exercise interventions to prevent falls in older people. In the benefit-harm trade-off method, hypothetical scenarios with the benefits, costs, risks and inconveniences associated with the intervention will be presented to each participant. Then, assuming a treatment effect of certain magnitude, the participant will be asked if he or she would choose to have the intervention. The size of the hypothetical benefit will be varied up and down until it is possible to identify the SWE for which the participant would choose to have the intervention. In the discrete choice experiment, the same attributes (benefits, costs, risks and inconveniences) with varying levels will be presented as choice sets, and participants will be asked to choose between these choice sets. With this approach, we will determine the probability that a person will consider the effects of an intervention to be worthwhile, given the particular costs, risks and inconveniences. For each of the two approaches, participants will be interviewed in person and on different occasions. A subsample of the total cohort will participate in both interviews. Ethics and dissemination: This project has received Ethics Approval from the University of Sydney Human Ethics Committee (Protocol number: 14404). Findings will be disseminated through conference presentations, seminars and peer-reviewed scientific journals

    One-carbon metabolism in cancer

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    Cells require one-carbon units for nucleotide synthesis, methylation and reductive metabolism, and these pathways support the high proliferative rate of cancer cells. As such, anti-folates, drugs that target one-carbon metabolism, have long been used in the treatment of cancer. Amino acids, such as serine are a major one-carbon source, and cancer cells are particularly susceptible to deprivation of one-carbon units by serine restriction or inhibition of de novo serine synthesis. Recent work has also begun to decipher the specific pathways and sub-cellular compartments that are important for one-carbon metabolism in cancer cells. In this review we summarise the historical understanding of one-carbon metabolism in cancer, describe the recent findings regarding the generation and usage of one-carbon units and explore possible future therapeutics that could exploit the dependency of cancer cells on one-carbon metabolism

    Statistical analysis plan for the COMPARE trial: a 3-arm randomised controlled trial comparing the effectiveness of Constraint-induced Aphasia Therapy Plus and Multi-modality Aphasia Therapy to usual care in chronic post-stroke aphasia (COMPARE)

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    BackgroundWhile high-quality meta-analyses have confirmed the effectiveness of aphasia therapy after stroke, there is limited evidence for the comparative effectiveness of different aphasia interventions. Two commonly used interventions, Constraint-induced Aphasia Therapy Plus (CIAT Plus) and Multi-modality Aphasia Therapy (M-MAT), are hypothesised to rely on diverse underlying neural mechanisms for recovery and may be differentially responsive to aphasia severity. COMPARE is a prospective randomised open-blinded end-point trial designed to determine whether, in people with chronic post-stroke aphasia living in the community, CIAT Plus and M-MAT provide greater therapeutic benefit compared to usual care, are differentially effective according to aphasia severity, and are cost-effective. This paper details the statistical analysis plan for the COMPARE trial developed prior to data analysis.MethodsParticipants (n = 216) are randomised to one of three arms, CIAT Plus, M-MAT or usual care, and undertake therapy with a study trained speech pathologist in groups of three participants stratified by aphasia severity. Therapy occurs for 3 h blocks per day for 10 days across 2 weeks. The primary clinical outcome is aphasia severity as measured by the Western Aphasia Battery-Revised Aphasia Quotient (WAB-R-AQ) immediately post intervention. Secondary outcomes include WAB-R-AQ at 12-week follow-up, and functional communication, discourse efficiency, multimodal communication, and health-related quality of life immediately post intervention and at 12-week follow-up.ResultsLinear mixed models (LMMs) will be used to analyse differences between M-MAT and UC, and CIAT-Plus and UC on each outcome measure immediately and at 12 weeks post-intervention. The LMM for WAB-R-AQ will assess the differences in efficacy between M-MAT and CIAT-Plus. All analyses will control for baseline aphasia severity (fixed effect) and for the clustering effect of treatment groups (random effect).DiscussionThis trial will provide relative effectiveness data for two common interventions for people with chronic post-stroke aphasia, and highlight possible differential effects based on aphasia severity. Together with the health economic analysis data, the results will enable more informed personalised prescription for aphasia therapy after stroke.Trial registrationAustralian New Zealand Clinical Trials Registry: ACTRN 12615000618550 . Registered on 15 June 2016

    Persistence of the immune response induced by BCG vaccination.

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    BACKGROUND: Although BCG vaccination is recommended in most countries of the world, little is known of the persistence of BCG-induced immune responses. As novel TB vaccines may be given to boost the immunity induced by neonatal BCG vaccination, evidence concerning the persistence of the BCG vaccine-induced response would help inform decisions about when such boosting would be most effective. METHODS: A randomised control study of UK adolescents was carried out to investigate persistence of BCG immune responses. Adolescents were tested for interferon-gamma (IFN-gamma) response to Mycobacterium tuberculosis purified protein derivative (M.tb PPD) in a whole blood assay before, 3 months, 12 months (n = 148) and 3 years (n = 19) after receiving teenage BCG vaccination or 14 years after receiving infant BCG vaccination (n = 16). RESULTS: A gradual reduction in magnitude of response was evident from 3 months to 1 year and from 1 year to 3 years following teenage vaccination, but responses 3 years after vaccination were still on average 6 times higher than before vaccination among vaccinees. Some individuals (11/86; 13%) failed to make a detectable antigen-specific response three months after vaccination, or lost the response after 1 (11/86; 13%) or 3 (3/19; 16%) years. IFN-gamma response to Ag85 was measured in a subgroup of adolescents and appeared to be better maintained with no decline from 3 to 12 months. A smaller group of adolescents were tested 14 years after receiving infant BCG vaccination and 13/16 (81%) made a detectable IFN-gamma response to M.tb PPD 14 years after infant vaccination as compared to 6/16 (38%) matched unvaccinated controls (p = 0.012); teenagers vaccinated in infancy were 19 times more likely to make an IFN-gamma response of > 500 pg/ml than unvaccinated teenagers. CONCLUSION: BCG vaccination in infancy and adolescence induces immunological memory to mycobacterial antigens that is still present and measurable for at least 14 years in the majority of vaccinees, although the magnitude of the peripheral blood response wanes from 3 months to 12 months and from 12 months to 3 years post vaccination. The data presented here suggest that because of such waning in the response there may be scope for boosting anti-tuberculous immunity in BCG vaccinated children anytime from 3 months post-vaccination. This supports the prime boost strategies being employed for some new TB vaccines currently under development

    A randomized control trial of intensive aphasia therapy after acute stroke: The Very Early Rehabilitation for SpEech (VERSE) study.

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    BACKGROUND:Effectiveness of early intensive aphasia rehabilitation after stroke is unknown. The Very Early Rehabilitation for SpEech trial (VERSE) aimed to determine whether intensive aphasia therapy, beginning within 14 days after stroke, improved communication recovery compared to usual care. METHODS:Prospective, randomized, single-blinded trial conducted at 17 acute-care hospitals across Australia/New Zealand from 2014 to 2018. Participants with aphasia following acute stroke were randomized to receive usual care (direct usual care aphasia therapy), or one of two higher intensity regimens (20 sessions of either non-prescribed (usual care-plus or prescribed (VERSE) direct aphasia therapy). The primary outcome was improvement of communication on the Western Aphasia Battery-Revised Aphasia Quotient (AQ) at 12 weeks after stroke. Our pre-planned intention to treat analysis combined high intensity groups for the primary outcome. FINDINGS:Among 13,654 acute stroke patients screened, 25% (3477) had aphasia, of whom 25% (866) were eligible and 246 randomized to usual care (n = 81; 33%), usual care-plus (n = 82; 33%) or VERSE (n = 83; 34%). At 12 weeks after stroke, the primary outcome was assessed in 217 participants (88%); 14 had died, 9 had withdrawn, and 6 were too unwell for assessment. Communication recovery was 50.3% (95% CI 45.7-54.8) in the high intensity group (n = 147) and 52.1% (95% CI 46.1-58.1) in the usual care group (n = 70; difference -1.8, 95% CI -8.7-5.0). There was no difference between groups in non-fatal or fatal adverse events (p = 0.72). INTERPRETATION:Early, intensive aphasia therapy did not improve communication recovery within 12 weeks post stroke compared to usual care
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